Space Science Reviews最新文献

{"title":"The Analyzer for Cusp Ions (ACI) on the TRACERS Mission.","authors":"Stephen A Fuselier, Matthew A Freeman, Craig A Kletzing, Sean R Christopherson, Michael J Covello, Daniel De Luna, Raymond L Doty, Colin G Elder, Judith D Furman, Jonathan Gasser, Don E George, Roman G Gomez, Guy A Grubbs, Kristie Llera, David M Miles, Joey Mukherjee, Kristian B Persson, Steven M Petrinec, Dinesh K V Radhakrishnan, Christopher L Ramirez, Ashley S Reisig, Charline Rodriguez, Courtney A Rouse, David A Ruggles, Shawn D Schwarz, Jonathan R Sekula, Linda J Shipp, Justyna M Sokół, Kylie M Sullivan, Karlheinz J Trattner, Sarah K Vines","doi":"10.1007/s11214-025-01154-w","DOIUrl":"10.1007/s11214-025-01154-w","url":null,"abstract":"<p><p>The Analyzers for Cusp Ions (ACIs) on the TRACERS mission measure ion velocity distribution functions in the magnetospheric cusp from two closely spaced spacecraft in low Earth orbit. The precipitating and upflowing ion measurements contribute to the overarching goal of the TRACERS mission and are key to all three science objectives of the mission. ACI is a toroidal top-hat electrostatic analyzer on a spinning platform that provides full angular coverage with instantaneous 22.5° × ∼6° angular resolution for a single energy step. ACI has an ion energy range from ∼8 eV/e to 20,000 eV/e covered in 47 logarithmic-spaced energy steps with fractional energy resolution of ∼10%. It provides reasonably high cadence (312 ms) measurements of the ion energy-pitch angle distribution with good sensitivity and energy resolution, enabling detection of cusp boundaries and characterization of cusp ion steps.</p>","PeriodicalId":21902,"journal":{"name":"Space Science Reviews","volume":"221 2","pages":"30"},"PeriodicalIF":9.8,"publicationDate":"2025-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11906535/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143650873","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"NASA'S <i>Lucy</i> Mission to Trojan Asteroids: Unraveling the History of the Outer Solar System.","authors":"Harold F Levison, Simone Marchi, Keith S Noll, John R Spencer, Catherine B Olkin, Thomas S Statler","doi":"10.1007/s11214-025-01173-7","DOIUrl":"10.1007/s11214-025-01173-7","url":null,"abstract":"<p><p><i>Lucy</i> is a NASA Discovery-class mission to send a highly capable and robust spacecraft to investigate primitive bodies near both the L₄ and L₅ Lagrange points with Jupiter; the Jupiter Trojan asteroids. This heretofore unexplored population of planetesimals from the outer planetary system holds vital clues to deciphering the history of the Solar System. Due to an unusual and fortuitous orbital configuration, <i>Lucy</i> will perform a comprehensive investigation that visits eight Trojans, including all the recognized taxonomic classes, a collisional family member and a near equal-mass binary. It will visit objects with diameters ranging from roughly 1 to 100 km. In particular, <i>Lucy</i> will perform flybys of (3548) Eurybates and its satellite Queta (L₄, C-type), (15094) Polymele and its currently unnamed satellite (L₄, P-type), (11351) Leucus (L₄, D-type), (21900) Orus (L₄, D-type), and the (617) Patroclus-Menoetius binary (L₅, P-types). This diverse array of targets will supply invaluable constraints on the formation and early dynamical evolution of the giant planets. In addition, <i>Lucy</i> will visit two main-belt asteroids, (152830) Dinkinesh and (52246) Donaldjohanson, in order to practice its encounters. <i>Lucy</i>'s payload suite consists of a color camera and infrared imaging spectrometer, a high resolution panchromatic imager, and a thermal infrared spectrometer. Additionally, two spacecraft subsystems will also contribute to the science investigations: the terminal tracking cameras will supplement imaging during closest approach and the telecommunication subsystem will be used to measure the mass of the Trojans. <i>Lucy</i> launched on October 16, 2021 and will have encounters with the Trojans from August 2027 until March 2033.</p>","PeriodicalId":21902,"journal":{"name":"Space Science Reviews","volume":"221 5","pages":"63"},"PeriodicalIF":7.4,"publicationDate":"2025-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC12226690/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144576319","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Mass Supply from Io to Jupiter's Magnetosphere.","authors":"Lorenz Roth, Aljona Blöcker, Katherine de Kleer, David Goldstein, Emmanuel Lellouch, Joachim Saur, Carl Schmidt, Darrell F Strobel, Chihiro Tao, Fuminori Tsuchiya, Vincent Dols, Hans Huybrighs, Alessandro Mura, Jamey R Szalay, Sarah V Badman, Imke de Pater, Anne-Cathrine Dott, Masato Kagitani, Lea Klaiber, Ryoichi Koga, Alfred S McEwen, Zachariah Milby, Kurt D Retherford, Stephan Schlegel, Nicolas Thomas, Wei-Ling Tseng, Audrey Vorburger","doi":"10.1007/s11214-025-01137-x","DOIUrl":"10.1007/s11214-025-01137-x","url":null,"abstract":"<p><p>Since the Voyager mission flybys in 1979, we have known the moon Io to be both volcanically active and the main source of plasma in the vast magnetosphere of Jupiter. Material lost from Io forms neutral clouds, the Io plasma torus and ultimately the extended plasma sheet. This material is supplied from Io's upper atmosphere and atmospheric loss is likely driven by plasma-interaction effects with possible contributions from thermal escape and photochemistry-driven escape. Direct volcanic escape is negligible. The supply of material to maintain the plasma torus has been estimated from various methods at roughly one ton per second. Most of the time the magnetospheric plasma environment of Io is stable on timescales from days to months. Similarly, Io's atmosphere was found to have a stable average density on the dayside, although it exhibits lateral (longitudinal and latitudinal) and temporal (both diurnal and seasonal) variations. There is a potential positive feedback in the Io torus supply: collisions of torus plasma with atmospheric neutrals are probably a significant loss process, which increases with torus density. The stability of the torus environment may be maintained by limiting mechanisms of either torus supply from Io or the loss from the torus by centrifugal interchange in the middle magnetosphere. Various observations suggest that occasionally (roughly 1 to 2 detections per decade) the plasma torus undergoes major transient changes over a period of several weeks, apparently overcoming possible stabilizing mechanisms. Such events (as well as more frequent minor changes) are commonly explained by some kind of change in volcanic activity that triggers a chain of reactions which modify the plasma torus state via a net change in supply of new mass. However, it remains unknown what kind of volcanic event (if any) can trigger events in torus and magnetosphere, whether Io's atmosphere undergoes a general change before or during such events, and what processes could enable such a change in the otherwise stable torus. Alternative explanations, which are not invoking volcanic activity, have not been put forward. We review the current knowledge on Io's volcanic activity, atmosphere, and the magnetospheric neutral and plasma environment and their roles in mass transfer from Io to the plasma torus and magnetosphere. We provide an overview of the recorded events of transient changes in the torus, address several contradictions and inconsistencies, and point out gaps in our current understanding. Lastly, we provide a list of relevant terms and their definitions.</p>","PeriodicalId":21902,"journal":{"name":"Space Science Reviews","volume":"221 1","pages":"13"},"PeriodicalIF":9.1,"publicationDate":"2025-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11799133/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143383263","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Solar Wind Magnetosphere Ionosphere Link Explorer (SMILE): Science and Mission Overview.","authors":"Chi Wang, Graziella Branduardi-Raymont, C Philippe Escoubet, Colin Forsyth","doi":"10.1007/s11214-024-01126-6","DOIUrl":"10.1007/s11214-024-01126-6","url":null,"abstract":"<p><p>The Solar wind Magnetosphere Ionosphere Link Explorer (SMILE) was proposed to the Chinese Academy of Science (CAS) and the European Space Agency (ESA) following a joint call for science missions issued in January 2015. SMILE was proposed by a team of European and Chinese scientists, led by two mission Co-PIs, one from China and one from Europe. SMILE was selected in June 2015, and its budget adopted by the Chinese Academy of Sciences in November 2016 and the ESA Science Programme Committee in March 2019, respectively. SMILE will investigate the connection between the Sun and the Earth using a new technique that will image the magnetopause and polar cusps: the key regions where the solar wind impinges on Earth's magnetic field. Simultaneously, SMILE will image the auroras borealis in an ultraviolet waveband, providing long-duration continuous observations of the northern polar regions. In addition, the ion and magnetic field characteristics of the magnetospheric lobes, magnetosheath and solar wind will be measured by the in-situ instrument package. Here, we present the science goals, instruments and planned orbit. In addition the Working Groups that are supporting the preparation of the mission and the coordination with other magnetospheric missions are described.</p>","PeriodicalId":21902,"journal":{"name":"Space Science Reviews","volume":"221 1","pages":"9"},"PeriodicalIF":9.8,"publicationDate":"2025-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11772532/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143068031","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"From Foreshock 30-Second Waves to Magnetospheric Pc3 Waves.","authors":"Lucile Turc, Kazue Takahashi, Primož Kajdič, Emilia K J Kilpua, Theodoros Sarris, Minna Palmroth, Jan Soucek, Yann Pfau-Kempf, Andrew Dimmock, Naoko Takahashi","doi":"10.1007/s11214-025-01152-y","DOIUrl":"10.1007/s11214-025-01152-y","url":null,"abstract":"<p><p>Ultra-low frequency waves, with periods between 1-1000 s, are ubiquitous in the near-Earth plasma environment and play an important role in magnetospheric dynamics and in the transfer of electromagnetic energy from the solar wind to the magnetosphere. A class of those waves, often referred to as Pc3 waves when they are recorded from the ground, with periods between 10 and 45 s, are routinely observed in the dayside magnetosphere. They originate from the ion foreshock, a region of geospace extending upstream of the quasi-parallel portion of Earth's bow shock. There, the interaction between shock-reflected ions and the incoming solar wind gives rise to a variety of waves, and predominantly fast-magnetosonic waves with a period typically around 30 s. The connection between these waves upstream of the shock and their counterparts observed inside the magnetosphere and on the ground was inferred already early on in space observations due to similar properties, thereby implying the transmission of the waves across near-Earth space, through the shock and the magnetopause. This review provides an overview of foreshock 30-second/Pc3 waves research from the early observations in the 1960s to the present day, covering the entire propagation pathway of these waves, from the foreshock to the ground. We describe the processes at play in the different regions of geospace, and review observational, theoretical and numerical works pertaining to the study of these waves. We conclude this review with unresolved questions and upcoming opportunities in both observations and simulations to further our understanding of these waves.</p>","PeriodicalId":21902,"journal":{"name":"Space Science Reviews","volume":"221 2","pages":"26"},"PeriodicalIF":9.1,"publicationDate":"2025-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11889074/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143586990","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Low-Temperature Aqueous Alteration of Chondrites.","authors":"Martin R Lee, Conel M O'D Alexander, Addi Bischoff, Adrian J Brearley, Elena Dobrică, Wataru Fujiya, Corentin Le Guillou, Ashley J King, Elishevah van Kooten, Alexander N Krot, Jan Leitner, Yves Marrocchi, Markus Patzek, Michail I Petaev, Laurette Piani, Olga Pravdivtseva, Laurent Remusat, Myriam Telus, Akira Tsuchiyama, Lionel G Vacher","doi":"10.1007/s11214-024-01132-8","DOIUrl":"10.1007/s11214-024-01132-8","url":null,"abstract":"<p><p>Chondritic meteorites (chondrites) contain evidence for the interaction of liquid water with the interiors of small bodies early in Solar System history. Here we review the processes, products and timings of the low-temperature aqueous alteration reactions in CR, CM, CI and ungrouped carbonaceous chondrites, the asteroids Ryugu and Bennu, and hydrated dark clasts in different types of meteorites. We first consider the nature of chondritic lithologies and the insights that they provide into alteration conditions, subdivided by the mineralogy and petrology of hydrated chondrites, the mineralogy of hydrated dark clasts, the effects of alteration on presolar grains, and the evolution of organic matter. We then describe the properties of the aqueous fluids and how they reacted with accreted material as revealed by physicochemical modelling and hydrothermal experiments, the analysis of fluid inclusions in aqueously formed minerals, and isotope tracers. Lastly, we outline the chronology of aqueous alteration reactions as determined using the ⁵³Mn-⁵³Cr and ¹²⁹I-¹²⁹Xe systems.</p><p><strong>Supplementary information: </strong>The online version contains supplementary material available at 10.1007/s11214-024-01132-8.</p>","PeriodicalId":21902,"journal":{"name":"Space Science Reviews","volume":"221 1","pages":"11"},"PeriodicalIF":9.1,"publicationDate":"2025-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11794400/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143365947","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Jets Downstream of Collisionless Shocks: Recent Discoveries and Challenges.","authors":"Eva Krämer, Florian Koller, Jonas Suni, Adrian T LaMoury, Adrian Pöppelwerth, Georg Glebe, Tara Mohammed-Amin, Savvas Raptis, Laura Vuorinen, Stefan Weiss, Niki Xirogiannopoulou, Martin Archer, Xóchitl Blanco-Cano, Herbert Gunell, Heli Hietala, Tomas Karlsson, Ferdinand Plaschke, Luis Preisser, Owen Roberts, Cyril Simon Wedlund, Manuela Temmer, Zoltán Vörös","doi":"10.1007/s11214-024-01129-3","DOIUrl":"10.1007/s11214-024-01129-3","url":null,"abstract":"<p><p>Plasma flows with enhanced dynamic pressure, known as magnetosheath jets, are often found downstream of collisionless shocks. As they propagate through the magnetosheath, they interact with the surrounding plasma, shaping its properties, and potentially becoming geoeffective upon reaching the magnetopause. In recent years (since 2016), new research has produced vital results that have significantly enhanced our understanding on many aspects of jets. In this review, we summarise and discuss these findings. Spacecraft and ground-based observations, as well as global and local simulations, have contributed greatly to our understanding of the causes and effects of magnetosheath jets. First, we discuss recent findings on jet occurrence and formation, including in other planetary environments. New insights into jet properties and evolution are then examined using observations and simulations. Finally, we review the impact of jets upon interaction with the magnetopause and subsequent consequences for the magnetosphere-ionosphere system. We conclude with an outlook and assessment on future challenges. This includes an overview on future space missions that may prove crucial in tackling the outstanding open questions on jets in the terrestrial magnetosheath as well as other planetary and shock environments.</p>","PeriodicalId":21902,"journal":{"name":"Space Science Reviews","volume":"221 1","pages":"4"},"PeriodicalIF":9.1,"publicationDate":"2025-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11680644/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142903543","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"The TRACERS Fluxgate Magnetometer (MAG).","authors":"Robert J Strangeway, Hao Cao, Eric Orrill, Ryan P Caron, David Pierce, Ryan Seaton, Henry H Gonzalez, Enrique Gurrola, William Greer, David Leneman, Michael J Lawson, Vicente Capistrano, Dean Bushong, Jianxin Chen, Cynthia L Russell, Jiashu Wu, David M Miles, Craig A Kletzing","doi":"10.1007/s11214-025-01212-3","DOIUrl":"10.1007/s11214-025-01212-3","url":null,"abstract":"<p><p>The NASA Tandem Reconnection and Cusp Electrodynamics Reconnaissance Satellites (TRACERS) mission is a two-spacecraft mission designed to explore the temporal and spatial signatures of magnetic reconnection as observed at the low altitude dayside cusp. The instrumentation on each TRACERS spacecraft includes a three-axis vector fluxgate magnetometer (MAG). The MAG sensor design heritage is from Magnetospheric Multiscale (MMS), while the electronics heritage is from the InSight mission to Mars. Testing as part of the MAG instrument delivery verified that the MAG dynamic range exceeded ±60,000 nT with a resolution of ∼9 pT to provide margin. The fluxgate magnetometers have been calibrated on the ground, but as is typical for fluxgates they will be re-calibrated using on-orbit data. The TRACERS spacecraft are spinning spacecraft in an orbit at 590 km altitude. Absolute gains, orientation, and spin-axis offsets will be determined through comparison with the International Geomagnetic Reference Field (IGRF) with an underlying orbit-period cadence. Additionally, spin-tones allow determination of relative angular orientation and gain and spin-plane offsets at spin-period temporal resolution. To meet the TRACERS mission science objectives MAG will measure magnetic field perturbations from large scale field-aligned currents, and shorter scale Alfvén waves. The electromagnetic energy flux associated with these magnetic field perturbations has major impacts on particle acceleration along the flux tube and ionospheric heating through Joule dissipation. This conversion from electromagnetic to particle energy is a primary driver for the escape of ionospheric plasma into the magnetosphere, making this an important secondary science objective for the TRACERS mission.</p>","PeriodicalId":21902,"journal":{"name":"Space Science Reviews","volume":"221 6","pages":"84"},"PeriodicalIF":9.8,"publicationDate":"2025-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC12431926/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145065550","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Physicochemical Controls on the Compositions of the Earth and Planets.","authors":"Paolo A Sossi, Remco C Hin, Thorsten Kleine, Alessandro Morbidelli, Francis Nimmo","doi":"10.1007/s11214-025-01243-w","DOIUrl":"10.1007/s11214-025-01243-w","url":null,"abstract":"&lt;p&gt;&lt;p&gt;Despite the fact that the terrestrial planets all formed from the protoplanetary disk, their bulk compositions show marked departures from that of material condensing from a canonical H&lt;sub&gt;2&lt;/sub&gt;-rich solar nebula. Metallic cores fix the oxygen fugacities ( &lt;math&gt;&lt;mi&gt;f&lt;/mi&gt;&lt;/math&gt; O&lt;sub&gt;2&lt;/sub&gt;s) of the planets to between ∼5 (Mercury) and ∼1 log units below the iron-wüstite (IW) buffer, orders of magnitude higher than that of the nebular gas. Their oxidised character is coupled with a lack of volatile elements with respect to the solar nebula. Here we show that condensates from a canonical solar gas at different temperatures ( &lt;math&gt;&lt;msub&gt;&lt;mi&gt;T&lt;/mi&gt; &lt;mn&gt;0&lt;/mn&gt;&lt;/msub&gt; &lt;/math&gt; ) produce bulk compositions with Fe/O (by mass) ranging from ∼0.93 ( &lt;math&gt;&lt;msub&gt;&lt;mi&gt;T&lt;/mi&gt; &lt;mn&gt;0&lt;/mn&gt;&lt;/msub&gt; &lt;mo&gt;=&lt;/mo&gt; &lt;mn&gt;1250&lt;/mn&gt;&lt;/math&gt;  K) to ∼0.81 ( &lt;math&gt;&lt;msub&gt;&lt;mi&gt;T&lt;/mi&gt; &lt;mn&gt;0&lt;/mn&gt;&lt;/msub&gt; &lt;mo&gt;=&lt;/mo&gt; &lt;mn&gt;400&lt;/mn&gt;&lt;/math&gt;  K), far lower than that of Earth at 1.06. Because the reaction Fe(s) + H&lt;sub&gt;2&lt;/sub&gt;O(g) = FeO(s) + H&lt;sub&gt;2&lt;/sub&gt;(g) proceeds only below ∼600 K, temperatures at which most moderately volatile elements (MVEs) have already condensed, oxidised planets are expected to be rich in volatiles, and vice-versa. That this is not observed suggests that planets &lt;math&gt;&lt;mi&gt;i&lt;/mi&gt; &lt;mo&gt;)&lt;/mo&gt;&lt;/math&gt; did not accrete from equilibrium nebular condensates and/or &lt;math&gt;&lt;mi&gt;i&lt;/mi&gt; &lt;mi&gt;i&lt;/mi&gt; &lt;mo&gt;)&lt;/mo&gt;&lt;/math&gt; underwent additional volatile depletion/ &lt;math&gt;&lt;mi&gt;f&lt;/mi&gt;&lt;/math&gt; O&lt;sub&gt;2&lt;/sub&gt; changes at conditions distinct from those of the solar nebula. Indeed, MVE abundances in small telluric bodies (Moon, Vesta) are consistent with evaporation/condensation at &lt;math&gt;&lt;mi&gt;Δ&lt;/mi&gt;&lt;/math&gt; IW-1 and ∼1400-1800 K, while the extent of mass-dependent isotopic fractionation observed implies this occurred near- or at equilibrium. On the other hand, the volatile-depleted elemental- yet near-chondritic isotopic compositions of larger telluric bodies (Earth, Mars) reflect mixing of bodies that had themselves experienced different extents of volatile depletion, overprinted by accretion of volatile-undepleted material. On the basis of isotopic anomalies in Cr- and Ti in the BSE, such undepleted matter has been proposed to be CI chondrites, which would comprise 40% by mass if the proto-Earth were ureilite-like. However, this would result in an overabundance of volatile elements in the BSE, requiring significant loss thereafter, which has yet to be demonstrated. On the other hand, 6% CI material added late to an enstatite chondrite-like proto-Earth would broadly match the BSE composition. However, because the Earth is an end-member in isotopic anomalies of heavier elements, no combination of existing meteorites alone can account for its chemical- and isotopic composition. Instead, the Earth is most likely made partially or essentially entirely from an NC-like missing component. If so, the oxidised-, yet volatile-poor nature of differentiated bodies in the inner solar system, including Ea","PeriodicalId":21902,"journal":{"name":"Space Science Reviews","volume":"221 8","pages":"118"},"PeriodicalIF":9.8,"publicationDate":"2025-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC12647311/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145640079","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Ohm's Law, the Reconnection Rate, and Energy Conversion in Collisionless Magnetic Reconnection.","authors":"Yi-Hsin Liu, Michael Hesse, Kevin Genestreti, Rumi Nakamura, James L Burch, Paul A Cassak, Naoki Bessho, Jonathan P Eastwood, Tai Phan, Marc Swisdak, Sergio Toledo-Redondo, Masahiro Hoshino, Cecilia Norgren, Hantao Ji, Takuma K M Nakamura","doi":"10.1007/s11214-025-01142-0","DOIUrl":"10.1007/s11214-025-01142-0","url":null,"abstract":"<p><p>Magnetic reconnection is a ubiquitous plasma process that transforms magnetic energy into particle energy during eruptive events throughout the universe. Reconnection not only converts energy during solar flares and geomagnetic substorms that drive space weather near Earth, but it may also play critical roles in the high energy emissions from the magnetospheres of neutron stars and black holes. In this review article, we focus on collisionless plasmas that are most relevant to reconnection in many space and astrophysical plasmas. Guided by first-principles kinetic simulations and spaceborne in-situ observations, we highlight the most recent progress in understanding this fundamental plasma process. We start by discussing the non-ideal electric field in the generalized Ohm's law that breaks the frozen-in flux condition in ideal magnetohydrodynamics and allows magnetic reconnection to occur. We point out that this same reconnection electric field also plays an important role in sustaining the current and pressure in the current sheet and then discuss the determination of its magnitude (i.e., the reconnection rate), based on force balance and energy conservation. This approach to determining the reconnection rate is applied to kinetic current sheets with a wide variety of magnetic geometries, parameters, and background conditions. We also briefly review the key diagnostics and modeling of energy conversion around the reconnection diffusion region, seeking insights from recently developed theories. Finally, future prospects and open questions are discussed.</p>","PeriodicalId":21902,"journal":{"name":"Space Science Reviews","volume":"221 1","pages":"16"},"PeriodicalIF":9.8,"publicationDate":"2025-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11811489/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143411103","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}